The GALEX satellite was launched in 2003 and continued its active mission until 2012. It is the first satellite to observe the entire sky with the two detectors, i.e. far ultraviolet (\(FUV\) , \(\lambda _{eff}\)  = 1528Å; 1344 - 1786Å) and near ultraviolet (\(NUV\) , \(\lambda _{eff}\)  = 2310Å; 1771 - 2831Å). The passbands of GALEX and UBV photometric systems are shown in Fig. 1. Measurements in the far and near UV bands of approximately 583 million objects obtained from the reduction of 100865 images from satellite observations are given in DR 6+7 versions of GALEX database [1]}. In our study, transformation equations between the colour indices of GALEX and UBV photometric systems are derived in terms of the luminosity class. These equations provide us empirical \(U-V\)  colour index and UV excess for stars which can be used in photometric metal abundance estimation. We organized the paper as follows. Section 2 is devoted to the selection of the calibration stars in our study, derivation of the calibrations is given in Section 3, and finally the results and discussion are presented in Section 4.
<FIGURE>